title: Flexural impact force absorption of mouthguard materials using film sensor system.
abstract: OBJECTIVE
  Several methods have been used to measure the impact force absorption capacities of mouthguard materials; however, the relationships among these measurement systems have not been clearly determined. The purpose of the present study was to evaluate the impact force-absorbing capability of materials using a drop-ball system with film sensors and load cells to clarify the relationship between these two sensor systems.
  
  
  METHODS
  Disk-shaped specimens (1, 2, and 3 mm thick) were prepared using three commercial thermoplastic mouthguard materials (Bioplast, Impact Guard, MG 21) and one experimental mouthguard material [mixture of Poly (ethyl methacrylate)]. Impact force was applied by letting a stainless steel ball drop free-fall onto the specimens and then measuring the impact load under each specimen using a film sensor system and a load cell sensor system.
  
  
  RESULTS
  The total load measured with the film sensor system decreased with an increase in mouthguard thickness, while almost none of the transmitted impact forces measured with the load cell system were statistically different.
  
  
  CONCLUSIONS
  The film sensor system was considered to be superior to the load cell system because the maximum stress and stress area could be determined.
authors.affiliation: Dental Biomaterials and Prosthodontics Unit, School of Dental Sciences, Universiti Sains Malaysia, Kubang Kerian, Malaysia.
authors.forename: Fazal
authors.initials: F
authors.lastname: Reza
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Churei
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Takahashi
authors.forename: Naohiko
authors.initials: N
authors.lastname: Iwasaki
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Ueno
mesh_terms: D008422:Materials Testing; D009064:Mouth Protectors
keywords: film sensor; impact force absorption; load cell; mouthguard